Medical and legal experts from around the world have united to call for more stringent regulation of stem cell therapies to prevent people pursuing unproven and potentially deadly treatments overseas.

In a perspective piece for the US journal Science Translational Medicine, 15 experts from countries including the UK, the US, Canada, Belgium, Italy and Japan wrote that national efforts alone would not be enough to counter an industry offering unproven treatments to vulnerable patients.

Stem cell-based interventions are classified under diverse and potentially incompatible national regulatory frameworks, the authors wrote.

Approaches for international regulation not only need to develop consistent rules over the commercialisation of medical practices and products but also need to give them teeth by developing cross-border partnerships for compliance.

Stem cells found in bone marrow and umbilical cord blood have long been used to successfully treat blood cancers including leukaemia and some immune diseases. But those are among the few proven treatments. Legitimate and ethics-approved clinical trials by academic centres are also occurring, exploring the potential of stem cells to treat a wider range of diseases.